JP2021528177A - Pressure support system and how to provide pressure support therapy to patients - Google Patents

Abstract

In a pressure support system (2) for providing pressure support therapy to a patient (10), a pressure support device is configured with an airflow generator (6) to generate a flow of respiratory gas to the patient, and the patient. Estimates and estimates the patient's core body temperature for a selected time based on a temperature control unit (29) configured to regulate the temperature of the respiratory gas provided to the patient and one or more inputs. Includes a processing unit (24) configured to control a temperature control unit to regulate the temperature of breath provided to the patient at a selected time based on the patient's core body temperature.

Description

The present invention relates to a pressure support system, and more particularly to a pressure support system that adjusts the respiratory gas temperature to a patient based on an estimated core body temperature.

Many people suffer from respiratory problems during sleep. Sleep apnea is a common example of such sleep apnea that millions of people around the world are suffering from. One type of sleep apnea is obstructive sleep apnea (OSA), a condition in which sleep is repeatedly interrupted by the inability to breathe due to obstruction of the airways; typically obstruction. Occurs in the upper respiratory tract or pharyngeal area. Airway obstruction is generally believed to allow, at least in part, the general relaxation of muscles that stabilize parts of the upper airway, thereby allowing tissue to collapse the airway. There is. Another type of sleep apnea syndrome is central apnea, which is respiratory arrest due to the lack of respiratory signals from the respiratory center of the brain. The apnea, whether obstructive, central, or a mixed form of a combination of obstructive and central, is a complete or near rest of breathing, eg, 90% or more of maximum respiratory flow. Defined as a decrease, etc.

People suffering from sleep apnea experience sleep fragmentation and intermittently complete or near-complete ventilation cessation, with the potential for severe hypohemoglobin saturation. These symptoms can be clinically translated as extreme daytime sleepiness, arrhythmias, pulmonary arterial hypertension, congestive heart failure, and / or cognitive dysfunction. Other results of sleep apnea include right ventricular dysfunction, carbon dioxide accumulation during sleep as well as awakening, and persistent reduction in arterial oxygen partial pressure. Those who suffer from sleep apnea may be at risk of excess mortality due to these factors, as well as a high risk of accidents while driving and / or operating potentially dangerous devices.

It is also known that even if the patient does not suffer from complete or near-complete airway obstruction, adverse effects such as awakening from sleep can occur if there is only partial airway obstruction. There is. Partial airway obstruction typically results in shallow breathing, called hypoventilation. Respiratory depression is typically defined as a 50% or greater reduction in maximal respiratory flow, followed by decreased oxyhemoglobin saturation and / or cortical arousal. Other types of sleep breathing disorders include, but are not limited to, upper airway resistance syndrome (UARS) and vibrations of the pharyngeal wall, commonly referred to as snoring.

Typically, an airway pressure support system containing a mask, a pressure generator, and a conduit for delivering positive pressure breathing gas through the mask from the pressure generator to the patient is used to enter the airway positive into the patient's airway. It is well known to treat sleep breathing disorders by applying pressure method (PAP). This positive pressure effectively "splints" the airways, thereby maintaining an open passage to the lungs. In one type of PAP therapy known as continuous positive airway pressure (CPAP), the pressure of the gas delivered to the patient is constant throughout the patient's respiratory cycle. It is also known to provide positive pressure therapy in which the pressure of the gas delivered to the patient changes with the patient's respiratory cycle or with the patient's respiratory effort to enhance patient comfort. This pressure support technique is called a bi-level pressure support method in which the inspiratory airway positive pressure (IPAP) delivered to the patient is higher than the expiratory airway positive pressure (EPAP). It is further known to provide positive pressure therapy in which the pressure is automatically adjusted based on the detected patient's condition, such as whether the patient is experiencing apnea and / or hypoventilation. This pressure support technique is called an automatic titration type pressure support method because the pressure support device strives to provide the patient with the pressure as high as necessary to treat the respiratory disorder.

The pressure support therapies described above include the placement of a patient interface device on the patient's face that includes a mask component with a soft and flexible sealing cushion. The mask component may be, without limitation, a nasal mask covering the patient's nose, a nose / mouth mask covering the patient's nose and mouth, or a full face mask covering the patient's face. Such patient interface devices may also utilize other patient contact components such as forehead supports, cheek pads, and chin pads. The patient interface device is typically secured to the patient's head by headgear components. The patient interface device is connected to a gas delivery tube or conduit and interfaces the pressure support device with the patient's airway, allowing the flow of respiratory gas to be delivered from the pressure / flow generator to the patient's airway.

It is important that pressure support therapy is comfortable for the patient. Unpleasant pressure support therapy can discourage patients from continuing this treatment. For example, a patient may be very compliant with PAP therapy but feels unwell or not refreshed when awake. This patient may suspect that this treatment is not working or that it is somehow adversely affecting sleep. Another example is a non-compliant patient. Non-compliance can be due to a number of reasons, one of which is that the patient does not believe that treatment will work for the patient, despite information from the referral physician. Each time a patient receives PAP therapy, he / she feels that his / her sleep quality is worse than when he / she does not, and therefore refuses to continue regular treatment.

Thermal intervention is applied passively or actively by physical exercise and induces significant changes in skin temperature and core body temperature (CBT). Not only is the intensity of thermal intervention critical, but the skin area selected and the timing / duration of application are also critical. In addition, CBT and skin temperature are very sensitive to changes in environmental temperature. Maximum total sleep time (TST) resides in the thermoneutral zone (the range of ambient temperatures in which temperature regulation is simply achieved by the vasomotor response), and REM and slow-wave sleep are vulnerable to thermal intervention. It is shown that there is. Thermal intervention can induce wakefulness and wakefulness, which can then have a temperature-regulating effect, for example by increasing CBT. When heat loads are repeatedly applied, the temperature control system can adapt and its effect on sleep changes. For example, the arousal effect is reduced.

Pressure support therapy can cause discomfort and thermal intervention in the patient that can induce arousal and wakefulness.

U.S. Pat. No. 5,148,802 U.S. Pat. No. 5,313,937 U.S. Pat. No. 5,433,193 U.S. Pat. No. 5,632,269 U.S. Pat. No. 5,803,065 U.S. Pat. No. 6,029,664 U.S. Pat. No. 6,539,940 U.S. Pat. No. 6,626,175 U.S. Pat. No. 7,011,091

In a pressure support system to provide pressure support therapy to a patient, a pressure support device: an airflow generator configured to generate a flow of respiratory gas to the patient; regulates the temperature of the respiratory gas delivered to the patient. Temperature control unit configured to Includes a processing unit configured to control the temperature control unit to regulate the temperature of the respiratory gas provided to the patient at the time.

How to provide pressure support therapy to a patient: the step of generating a flow of respiratory gas to the patient; the step of receiving one or more inputs; the patient's at a selected time based on one or more inputs. It includes the step of estimating the core body temperature; and the step of adjusting the temperature of the respiratory gas provided to the patient at a selected time based on the estimated core body temperature of the patient.

When a non-temporary computer-readable medium is executed by a computer, it stores one or more programs containing instructions that cause the computer to perform a method of providing pressure support therapy to the patient. The method is: the step of generating a flow of respiratory gas to the patient; the step of receiving one or more inputs; the step of estimating the patient's core body temperature for a selected time based on one or more inputs; And, the step of adjusting the temperature of the respiratory gas provided to the patient at a selected time based on the estimated core body temperature of the patient;

FIG. 5 is a graph showing CBT of pre-sleep and sleeping patients according to an exemplary embodiment of the disclosed concept. FIG. 6 is a schematic representation of an airway pressure support system according to an exemplary embodiment of the disclosed concept. It is a schematic diagram of a part of a pressure support system according to an exemplary embodiment of the disclosed concept. It is a figure which showed the graph which shows the two-process model of arousal. It is a figure which showed the graph which shows the correlation between CBT and various features with the passage of time. It is a flow chart of a method of providing a pressure support therapy to a patient according to an exemplary embodiment of the disclosed concept.

As used herein, singular indefinite articles and definite articles include their plural unless their content explicitly indicates something else. As used herein, the statement that two or more parts or components are "connected" means that the parts are joined together or directly or indirectly, i.e., as long as concatenation occurs. It means working together through one or more intermediate parts or components. As used herein, "directly linked" means that the two elements are in direct contact with each other. As used herein, "fixed and connected" or "fixed" means that the two components move as one while maintaining a constant orientation with respect to each other. Means to be done.

As used herein, the word "unitary" means that the components are made as single pieces or units. That is, a component that includes components that are manufactured separately and then connected together as a unit is not a "single structure" component or a "single structure" body. As used herein, the statement that two or more parts or components "mesh / engage" with each other means that the parts are directly or through one or more intermediate parts or components. It means exerting force on it. As used herein, the term "number" means an integer (ie, plural) greater than or equal to one or one.

For example, without limitation, phrases indicating directions used herein, such as up, down, left, right, up, down, front, back, and derivatives thereof, are the orientations of the elements shown in the drawings. The scope of claims is not limited unless it is clearly stated.

The respiratory gas provided in pressure support therapy is typically provided at a constant temperature. The temperature of the breathing gas may be comfortable at one time (ie, one time in a 24-hour cycle), but the temperature of the breathing gas may not be comfortable for the patient at another time. For example, the temperature of the breathing gas can be comfortable in the evening, but can be unpleasant at later times from midnight to morning.

FIG. 1 is a graph showing CBT of patients before and during sleep. In the graph, the time after turning off indicates the approximate time the patient fell asleep. For example, 0 hours after turning off indicates the approximate time that the patient fell asleep, and 4 hours after turning off indicates that it is 4 hours from the approximate time that the patient fell asleep. As shown in FIG. 1, the patient's CBT drops to the lowest point about 5 hours after the patient falls asleep and then begins to rise again.

The respiratory gas provided to the patient at a constant temperature at the beginning of the sleep period may be comfortable for the patient at first, but due to the decrease in the patient's CBT during the sleep period, the temperature of the respiratory gas and the patient's CBT The change in the difference can be uncomfortable for the patient in the middle of the sleep period. Although the temperature of the respiratory gas remains the same, the respiratory gas can cause thermal intervention and discomfort due to changes in the patient's CBT. This discrepancy will change throughout the night and can adversely affect sleep initiation, sleep maintenance, and sleep continuity. The temperature of the conduit that provides the patient with respiratory gas can also cause discomfort when in contact with the patient's skin at night. Mismatches between the temperature of the respiratory gas or conduit and the patient's CBT, which changes throughout the night, can disrupt sleep continuity, increase sleep fragmentation, and lead to complaints of morning / noon fatigue.

Human thermoregulation is primarily controlled by circadian rhythms and sleep regulation. Humans have a sleep-wake rhythm that repeats in a cycle of approximately 24 hours. According to the circadian rhythm, CBT decreases during the sleep phase and rises during the repetitive wake phase. According to some exemplary embodiments of the disclosed concept, the temperature of the respiratory gas provided to the patient is adjusted based on the estimated core body temperature of the patient.

FIG. 2 is a schematic representation of an airway pressure support system 2 according to one particular non-limiting and exemplary embodiment in which the present invention can be practiced. Referring to FIG. 2, the airway pressure support system 2 includes a pressure support device 4 that houses an airflow generator 6 such as a blower used in conventional CPAP or bi-level pressure support devices. The pressure generator 6 receives the breathing gas generally indicated by the arrow C from the ambient air through the filtered intake port 8 provided as part of the pressure support device 4, and has relatively high and low pressures, i.e., generally. To generate a flow of respiratory gas from it to deliver to the airway of the patient 10 at a pressure equal to or greater than the ambient pressure to provide pressure compensation to the patient 10 via the patient circuits 12 and 14. Generate pressure. In an exemplary embodiment, the airflow generator 6 is capable of providing a flow of respiratory gas with a pressure ranging from 3 to 30 cmH2O. The pressurized flow of respiratory gas from the airflow generator 6, generally indicated by arrow D, is delivered via the delivery conduit 12 to a respiratory mask or patient interface 14 of any known configuration, which respiratory mask or interface. Is typically worn by the patient 10 or otherwise attached to the patient 10 to direct the flow of respiratory gas into the airways of the patient 10. The delivery conduit 12 and the patient interface device 14 are typically collectively referred to as the patient circuit.

The pressure support system 2 shown in FIG. 2 is known as a single rim system, meaning that the patient circuit includes only the delivery conduit 12 that connects the patient 10 to the pressure support system 2. .. As such, as indicated by arrow E, an exhaust port 16 for expelling exhaled gas from the system is provided within the delivery conduit 12. It should be noted that the exhaust port 16 can be provided in other locations in addition to or in place of the delivery conduit 12, such as in the patient interface device 14. It should also be appreciated that the exhaust port 16 may have a wide variety of configurations, depending on the desired mode in which the gas will be discharged from the pressure support system 2.

The concept also considers that the pressure support system 2 may be a two-rim system with a delivery conduit and an exhaust conduit connected to the patient 10. In a two-rim system (also called a dual rim system), the exhaust conduit carries the exhaust gas from the patient 10 and includes an exhaust valve at the end distal to the patient 10. The exhaust valve in such an embodiment is typically actively controlled to maintain the desired level or pressure in a system commonly known as positive end-expiratory pressure ventilation (PEEP).

Further, in the illustrated exemplary embodiment shown in FIG. 1, the patient interface 14 is a nasal / mouth mask. However, it will be understood that the patient interface 14 may include a nasal mask, a nasal pillow, a tracheal tube, an endotracheal tube, or any other device that provides suitable gas flow transmission function. Also, for the purposes of the present invention, the phrase "patient interface" may include any other structure that binds the delivery conduit 12 and the pressurized respiratory gas source to the patient 10.

In the illustrated embodiment, the pressure support system 2 includes a pressure control device in the form of a valve 18 provided in the internal delivery conduit 20 provided in the housing of the pressure support device 4. The valve 18 controls the pressure of the respiratory gas flow from the airflow generator 6 delivered to the patient 10. For this purpose, the airflow generator 6 and valve 18 are collectively referred to as a pressure generating system because they work together to generate and control the pressure and / or flow of gas delivered to patient 10. However, other techniques for controlling the pressure of the gas delivered to the patient 10, such as changing the speed of the blower of the airflow generator 6 alone or in combination with a pressure control valve, are considered by the present invention. Should be clear. Therefore, the valve 18 is optional, depending on the technique used to control the pressure of the respiratory gas flow delivered to the patient 10. When the valve 18 is removed, the pressure generating system corresponds only to the airflow generator 6, and the pressure of the gas in the patient circuit is controlled, for example, by controlling the motor speed of the airflow generator 6.

The pressure support system 2 further includes a flow sensor 22 that measures the flow rate of respiratory gas in the delivery conduit 20 and the delivery conduit 12. In the particular embodiment shown in FIG. 1, the flow sensor 22 is inserted in line with the delivery conduits 20 and 12, most preferably downstream of the valve 18. The pressure support system 2 also includes a pressure sensor 27 that detects the pressure of the pressurized fluid in the delivery conduit 20. Although the point at which the flow rate is measured by the flow sensor 22 and the pressure is measured by the pressure sensor 27 is exemplified as being in the pressure support device 4, the position where the actual flow rate and pressure measurement is performed is the delivery conduit 20. Or it should be understood that it may be in any position along 12. The flow rate of respiratory gas measured by the flow sensor 22 and the pressure detected by the pressure sensor 27 are provided to the processing unit 24 to determine _{the flow rate of gas (Q PAIENT) in the patient 10.}

_Techniques for calculating Q PATION are well known, such as pressure drops in the patient circuit, known leaks from the system, ie intentional gas discharge from the circuit as indicated by arrow E in FIG. And take into account unknown leaks from the system, such as leaks in the mask / patient interface. The present invention uses any known or upcoming technique for calculating _{leakflow, and uses this determination in calculating QPATIENT using measured flow rates and pressures.} I'm pondering what to do. Examples of such techniques are taught in Patent Documents 1-9, the respective contents of which are incorporated herein by reference.

Of course, without limitation, measuring the flow rate directly at the patient 10 or elsewhere along the delivery conduit 12, measuring the patient flow rate based on the operation of the gas flow generator 6, and upstream of the valve 18. Other techniques for measuring the respiratory flow rate of the patient 10, such as measuring the patient flow rate using the flow sensor of the above, are considered by the present invention.

The input / output device 26 is provided to set various parameters used by the pressure support system 2 and to display and output information and data to a user such as a clinician or a caregiver.

The pressure support system 2 further includes a temperature sensor 28 that measures the temperature of the respiratory gas provided to the patient 10. The temperature sensor 28 may be included in or in close proximity to the patient interface device 14 to measure the temperature of the respiratory gas in the patient 10. However, it will be correctly understood that the temperature sensor 28 may be located elsewhere, such as within the pressure support device 4 or the conduit 12, without departing from the scope of the disclosed concepts. It will also be correctly understood that a plurality of temperature sensors 28 may be provided without departing from the scope of the disclosed concepts.

The pressure support system 2 also includes a temperature control unit 29. The temperature control unit 29 is configured to regulate the temperature of the respiratory gas provided to the patient 10. In some exemplary embodiments, the temperature control unit 29 may be a heating unit configured to heat the respiratory gas provided to the patient 10. For example, without limitation, the temperature control unit 29 may include a resistance heating element extending along the conduit 12. Passing power through the resistance heating element heats the resistance heating element and thus the breathing gas provided to the patient 10 through the conduit 12. However, it is correctly understood that other types of heating units configured to heat the respiratory gas provided to patient 10 may be used without departing from the scope of the disclosed concepts. become. In some exemplary embodiments of the disclosed concepts, the temperature control unit 29 may be configured to cool the respiratory gas provided to the patient 10. For example, in some environments, the temperature of the ambient air can be higher than the temperature that is comfortable for the patient 10, so it is beneficial to cool the respiratory gas. In some exemplary embodiments, the temperature control unit 29 may be configured to selectively heat and cool the respiratory gas provided to the patient 10.

The processing unit 24 estimates the CBT of patient 10 for a selected time based on one or more inputs, and at a selected time based on the estimated CBT of patient 10 at a selected time. The temperature control unit 29 is configured to control the temperature of the breathing gas provided to the patient 10. For example, the change in CBT during the selected time may be determined, and the temperature of the respiratory gas may be adjusted by the same amount as the change in CBT between the selected time. For example, without limitation, the processing unit 24 can estimate that the CBT of patient 10 will drop by 0.25 ° C. per hour between 10 pm and 2 am. Correspondingly, the processing unit 24 adjusts the temperature of the respiratory gas provided to patient 10 by only 0.25 ° C. per hour between 10 pm and 2 am to match the estimated decrease in CBT of patient 10. The temperature control unit 29 can be controlled so as to lower it.

It will be correctly understood that the time chosen by the processing unit 24 to estimate the patient 10's CBT may be up to and at any time including the continuous estimation of the patient's CBT. The selected time may be during the target period of the day or over the entire 24 hours. It is said that the processing unit 24 can control the temperature adjusting unit 29 to adjust the temperature of the respiratory gas provided to the patient 10 based on the estimated CBT up to continuously and at any frequency including it. That will also be understood correctly. It is also correctly understood that the estimated temperature resolution of the CBT and temperature control unit 29 (ie, the minimum change in temperature) may be any quantity without departing from the scope of the disclosed concepts. become. The processing unit 24 can use the output from the temperature sensor 28 to ensure that the target temperature of the respiratory gas provided to the patient 10 has been reached.

In the exemplary embodiment shown in FIG. 2, the processing unit 24 is included in the pressure support device 4. However, the processing unit 24 may be located outside the pressure support device 24, such as inside a server or other external computing device, or may be distributed between the pressure support device 4 and one or more external devices. It will be correctly understood that it is okay. For example, the processing unit 24 may be distributed so as to include a component that controls the temperature control unit 29 in the pressure support device 29 and a component that estimates the CBT of the patient 10 in the external device.

The processing unit 24 estimates the CBT of patient 10 at a selected time based on one or more inputs. Some examples of inputs are given in conjunction with FIG.

FIG. 3 is a schematic diagram of a portion of the pressure support system 2 according to an exemplary embodiment of the disclosed concept. A processing unit 24 according to an exemplary embodiment of the disclosed concept is shown in more detail in FIG.

The processing unit 24 includes a processor 30, a memory 32, and a communication unit 34. The processor 30 can form, for example, all or part of a processing portion that can be a microprocessor, a microcontroller, or some other suitable processing device. The memory 32 can form all or part of a memory portion that can be inside the processing portion or can be operably coupled to the processing portion, and further performs the function of the processing unit 23 to provide a pressure support system. It is possible to provide a storage medium for software and data that can be executed by the processing portion to control the operation of 2. The memory 32 is in the form of various types of internal and / or external storage media such as RAM, ROM, EPROM, EEPROM, and FLASH, i.e., the internal storage area of a computer, which provides storage registers without limitation. It may be either one or a plurality of machine-readable media for data storage such as those, and may be a volatile memory or a non-volatile memory.

The communication unit 34 can provide communication between the processing unit 24 and another component of the pressure support device 4, a component of the patient circuit, or another external device. For example, without limitation, the communication unit 34 can facilitate communication with various sensors such as the temperature sensor 29. The communication unit 34 can also facilitate communication with an external device. For example, without limitation, the communication unit 34 can facilitate communication with electronic devices such as telephones, tablets, computers, or other devices, either directly or over a network. The communication facilitated by the communication unit 34 may allow the processing unit 24 to send and receive data from the components or devices with which it communicates.

The state of the circadian clock cannot be evaluated directly in humans and usually relies on indirect measurements that are closely related to the activity of the circadian clock itself. Thermoregulation in general, and especially CBT, is closely associated with circadian rhythms, but is difficult to estimate easily and accurately. Measurements usually rely on an ingestible thermometer or rectal thermometer.

Another marker of circadian rhythm phase is melatonin levels, which are primarily affected by exposure to bright light. Given its relative resilience to the masking effect, melatonin secretion start time (DLMO) is the most practical indicator of the circadian phase. However, this relies on the measurement of melatonin levels in repetitive saliva samples. This is impractical for home use and for continued use. Other features of patient 10 can be monitored to estimate the circadian rhythm of patient 10. Since the circadian rhythm is closely related to CBT, the estimated patient 10 circadian rhythm can be used to estimate the patient's CBT at a selected time.

Heart rate variability is one feature that can be used to estimate the circadian rhythm of patient 10. For example, the heart rate of patient 10 drops during the sleep phase. The heart rate sensor 35 can be used to monitor the heart rate of patient 10. The heart rate sensor 25 may be, for example, a photoplethysmogram (PPG) or other type of heart sensor worn on the wrist without limitation. The heart rate sensor 35 can detect the heart rate of the patient 10 for several days, and the processing unit 24 can estimate the sleep phase of the patient 10 from the sensed heart rate. From the estimated sleep phase, the processing unit 24 can estimate the circadian rhythm and CBT of patient 10.

Body movement is another feature that can be used to estimate the circadian rhythm of patient 10. During the sleep phase of patient 10, patient 10 has little or no body movement. The body movement sensor 36, such as a wristband, wristwatch, or other device worn by the patient 10, can be used to detect the body movement of the patient 10. Sensing body movements is sometimes called actigraphy. The body movement sensor 36 can detect the body movement of the patient 10 for several days, and the processing unit 24 can estimate the circadian rhythm and the CBT of the patient 10 from the sensed body movement. ..

Light level exposure is another feature that can be used to estimate the circadian rhythm of patient 10. For example, the perception when the patient 10 is in a dark environment (eg, a darkened bedroom, etc.) can be used to estimate when the patient 10 is in the sleeping phase. The light sensor 37 may be used to detect when the patient 10 is in a dark environment. For example, the optical sensor 37 may be a wearable device such as a wristband or wristwatch, or may be integrated into the wearable device. The optical sensor 37 can detect the exposure amount of the patient 10 for several days, and the processing unit 24 can estimate the circadian rhythm and the CBT of the patient 10 from the sensed exposure amount.

Distal skin temperature is another feature that can be used to estimate the circadian rhythm of patient 10. The temperature of the distal region of the patient 10's body, such as within the region of the hand or foot, can be used to estimate when the patient 10 is in sleep phase. The distal skin temperature of patient 10 rises before patient 10 enters the sleep phase and CBT decreases. A skin temperature sensor 38, such as a wristband sensor, worn by the patient 10 can be used to sense the distal skin temperature of the patient 10 for several days, from which the treated distal temperature the processing unit 24 can sense. The circadian rhythm and CBT of patient 10 can be estimated.

The presence or absence of patient 10 in bed is another feature that can be used to estimate the circadian rhythm of patient 10. For example, the time that patient 10 is in bed can be used to estimate the sleep phase of patient 10. Bed sensor 39 is used to detect the presence or absence of patient 10 in bed over several days, such as a weight sensor located under the mattress or any other type of sensor suitable for detecting the presence or absence of patient 10 in bed. The processing unit 24 can estimate the circadian rhythm and CBT of patient 10 from the presence or absence in the sensed bed.

In some exemplary embodiments, the ballistic geography sensor 40 can be placed above or below the patient 10's mattress to measure the patient's heart rate while the patient 10 is in bed. As mentioned above, the heart rate of patient 10 decreases as patient 10 enters the sleep phase. The processing unit 24 can estimate the circadian rhythm and CBT of the patient 10 from the output of the ballistic geography sensor 40.

In some exemplary embodiments, the processing unit 24 estimates the patient 10's CBT based on the sensed patient 10 head temperature. For example, the head temperature sensor 41 can be used to sense the temperature in the area of the patient 10's head. The head temperature sensor 41 may be integrated into a component of the pressure support system 2, such as a mask strap across the frontal region of the patient 10. Based on the perceived temperature of the patient 10's head, the processing unit 24 can estimate the patient 10's CBT.

The output of any of the sensors 35-41 can be used as an input to the processing unit 24 to estimate the CBT of patient 10 at a selected time. It will be correctly understood that FIG. 3 merely illustrates examples of different types of sensors that can be used as inputs to the processing unit 24. One or a subset of sensors 35-41 may be used as input to the processing unit 24 for estimating CBT for patient 10, and the rest of sensors 35-41 deviates from the scope of the disclosed concepts. Removed without. It will also be correctly understood that sensors 35-41 are merely examples and that other types of sensors can be utilized without departing from the scope of the disclosed concepts. Sensors 35-41 sense patient 10 features that correlate with patient 10's CBT. Without departing from the scope of the disclosed concepts, the processing unit 24 can also receive input from any other type of sensor that senses patient 10 features that correlate with patient 10's CBT. It will be understood correctly.

The sensors 35-41 may be directly connected to the processing unit 24 via a direct connection to the pressure support device 4, or the sensors 35-41 may be separated from the processing unit 24 and periodically connected to the processing unit 24. Connected, the sensed data may be provided to the processing unit 24 via one or more intermediate devices. For example, if the heart rate sensor 35 is a wristband worn by the patient 10, the heart rate sensor 35 can be connected to a device such as a telephone or tablet, and the device such as a telephone or tablet is then the processing unit. It can be connected to 24 and provide the sensed data to the processing unit 24. As another example, the bed sensor 39 can be expected to stay in the bed of the patient 10 by the pressure support device 4, so that the bed sensor 39 connects directly to the processing unit 24 via a connection to the pressure support device 4. May be done.

In addition to or in lieu of inputs from one or more of sensors 35-41, the unit of processing unit 24 is profiled as input used to estimate the CBT of patient 10 at a selected time. Can be received. The profile information may include, for example, without limitation, the gender, age, or personal preference of patient 10. The profile information may be input to an external device such as a telephone, tablet, or computer and communicated to the processing unit 24.

FIG. 4 is a graph showing a two-process model of arousal. FIG. 4 illustrates the interaction between process S (homeostatic sleep pressure), process C (circadian rhythm), and periods of arousal and sleep. As shown in FIG. 4, the sleep phase occurs daily during approximately the same points in the circadian rhythm. Based on the correlation between the sleep phase and the circadian rhythm, the sleep phase estimation can be used to estimate the circadian rhythm of patient 10, and thus the CBT of patient 10.

FIG. 5 is a graph showing the correlation between CBT and various features over a period of time centered around when the lights are turned off (ie, approximately when the patient falls asleep). The upper part of FIG. 5 shows the patient's distal proximal gradient (ie, the difference between the patient's distal and proximal temperatures), proximal temperature, and distal temperature in degrees Celsius. The central part of FIG. 5 shows the patient's drowsiness on the Karolinska Drowsiness Scale and the patient's salivary melatonin levels in picograms per milliliter. The bottom of FIG. 5 shows CBT in degrees Celsius and the patient's heart rate in beats per minute. As can be seen from FIG. 5, various features lead to or during the sleep phase in which CBT is reduced. As such, these features correlate with CBT during sleep phases and can be used to estimate CBT during sleep phases.

FIG. 6 is a flow diagram of a method of providing pressure support therapy to a patient according to an exemplary embodiment of the disclosed concept. The method can be carried out, for example, without limitation in the pressure support system 2 shown in FIGS. 2 and 3, and is described with respect to the pressure support system 2 shown in FIGS. 2 and 3. become. However, it will be correctly understood that the method can be implemented in other types of pressure support systems without departing from the scope of the disclosed concepts.

The method begins at 50, where a stream of respiratory gas provided to the patient is generated. The flow of respiratory gas may be generated, for example, by an airflow generator 6 or other device capable of generating airflow. At 51, one or more inputs are received. One or more inputs may be received by the processing unit 24 or other similar device. At 52, the CBT of patient 10 is estimated for a selected time based on the input received. The input may be, for example, without limitation, an input from sensors 35-41, profile information of patient 10, or any other input of patient 10 features that correlates with the patient's circadian rhythm. At 53, the temperature of the respiratory gas provided to patient 10 is adjusted based on the estimated CBT. For example, the change in CBT during the selected time may be determined, and the temperature of the respiratory gas may be adjusted by the same amount as the change in CBT between the selected time. The temperature can be adjusted by the temperature control unit 29, or the processing unit 24 or a similar device under the control of a similar device.

It is pondered that aspects of the disclosed concept can be embodied as computer-readable code on tangible computer-readable recording media. A computer-readable recording medium is any data storage device capable of storing data, which can then be read by a computer system. Examples of computer-readable recording media include read-only memory (ROM), random access memory (RAM), CD-ROM, magnetic tape, floppy disk, and optical data storage device.

Within the scope of claims, any reference number placed in parentheses should not be construed as limiting the scope of claims. The word "comprising or including" does not preclude the existence of elements or steps other than those stated in the claims. In a device claim that lists several means, some of these means can be implemented by one and the same hardware item. If an indefinite article is used when referring to an element of a singular noun, it does not exclude the existence of the plural form of such element. Even in the claims of any device that lists several means, some of these means can be realized by one and the same hardware item. The mere fact that certain elements are listed in different dependent terms does not indicate that these elements cannot be used in combination.

Although the present invention has been described in detail for purposes of illustration based on what is currently considered to be the most practical and preferred embodiment, such details are solely for that purpose and the present invention is described. It should be understood that, but not limited to, the disclosed embodiments, on the contrary, it is intended to cover the intent and amendments and equivalent configurations within the scope of the accompanying claims. For example, it should be understood that the present invention contemplates that, wherever possible, one or more features of any embodiment can be combined with one or more features of any other embodiment.

Thermal intervention is applied passively or actively by physical exercise and induces significant changes in skin temperature and core body temperature (CBT). Not only is the intensity of thermal intervention critical, but the skin area selected and the timing / duration of application are also critical. In addition, CBT and skin temperature are very sensitive to changes in environmental temperature. Maximum total sleep time (TST) resides in the thermoneutral zone (the range of ambient temperatures in which temperature regulation is simply achieved by the vasomotor response), and REM and slow-wave sleep are vulnerable to thermal intervention. It is shown that there is. Thermal intervention can induce wakefulness and wakefulness, which can then have a temperature-regulating effect, for example by increasing CBT. When heat loads are repeatedly applied, the temperature control system can adapt and its effect on sleep changes. For example, the arousal effect is reduced.
WO 2010/090509 (A1) discloses a respiratory device and method for providing a person with cooling breathing gas. This breathing apparatus provides a breathing gas containing an additive in the form of droplets or frozen particles. The breathing apparatus provides a gas regulating conduit, a gas propulsion means for generating a flow of respiratory gas through the gas regulating conduit, an additive, preferably an additive injecting means for injecting water droplets or ice particles into the gas regulating conduit. include. Cooling means are provided to cool the respiratory gas and additives while being carried through the gas regulating conduit, and a mask is provided to provide the respiratory gas to the human respiratory tract, preferably through the nose. Will be done. The respiratory system is such that the heat transfer from the body of the person breathing the breathing gas to the breathing gas and additives is high enough to stimulate the person's metabolism and burn more energy, causing the body to become hypothermic. It also includes a control system to control the respiratory system so that it is low enough to prevent it from becoming.
WO 2015/035315 (A2) discloses a therapeutic system that includes a delivery device that delivers a combination of respiratory gas and frozen ice or other particles to a patient to induce hypothermia. This treatment system adjusts the temperature system for measuring the temperature of the exhaled gas and the duration or rate at which the ice particles are delivered to control the patient's deep temperature based on the measured exhaled gas temperature. Also includes controllers that can.

Claims (19)

A pressure support system for providing pressure support therapy to patients, and the pressure support device
An airflow generator configured to generate a flow of respiratory gas to the patient,
A temperature control unit configured to regulate the temperature of the breathing gas provided to the patient.
Based on one or more inputs, the patient's core body temperature is estimated for a selected time, and based on the estimated patient's core body temperature, the respiration provided to the patient at the selected time. A processing unit configured to control the temperature control unit in order to control the temperature of the
Pressure support system, including. The processing unit determines the estimated change in the patient's core body temperature during the selected time and controls the temperature control unit to control the estimated temperature over the patient's core body temperature during the selected time. The pressure support system according to claim 1, wherein the pressure support system is configured to adjust the temperature of the respiratory gas provided to the patient by the same amount as the change in. The pressure support system of claim 1, wherein the one or more inputs include profile information of the patient. The pressure support system according to claim 3, wherein the profile information includes at least one of the patient's gender, age, and personal preference. The pressure support system according to claim 1, wherein the one or more inputs include inputs from one or more sensors. The pressure support system according to claim 5, wherein the one or more sensors include one or more sensors configured to sense the patient's characteristics that correlate with the patient's circadian rhythm. The pressure support system according to claim 6, wherein the one or more sensors include at least one of a heart rate sensor, a body movement sensor, an optical sensor, and a distal skin temperature sensor. The pressure support system according to claim 6, wherein the one or more sensors include at least one of a bed sensor and a ballistic geography sensor. The pressure support system according to claim 5, wherein the one or more sensors include a head temperature sensor configured to sense the temperature of the patient's head. A way to provide pressure support therapy to patients
The steps to generate the flow of respiratory gas to the patient,
With the step of receiving one or more inputs,
A step of estimating the patient's core body temperature for a selected time based on one or more of the inputs.
A step of adjusting the temperature of the respiratory gas provided to the patient at the selected time based on the estimated core body temperature of the patient.
How to include. The step of determining the estimated change in core body temperature of the patient during the selected time and
A step of adjusting the temperature of the respiratory gas provided to the patient by the same amount as the estimated change in the patient's core body temperature between the selected times.
10. The method of claim 10. The method of claim 10, wherein the one or more inputs include profile information of the patient. 12. The method of claim 12, wherein the profile information comprises at least one of the patient's gender, age, and personal preference. 10. The method of claim 10, wherein the one or more inputs include inputs from one or more sensors. 14. The method of claim 14, wherein the one or more sensors include one or more sensors configured to sense the patient's characteristics that correlate with the patient's circadian rhythm. 15. The method of claim 15, wherein the one or more sensors comprises at least one of a heart rate sensor, a body movement sensor, an optical sensor, and a distal skin temperature sensor. 15. The method of claim 15, wherein the one or more sensors comprises at least one of a bed sensor and a ballistic geography sensor. 14. The method of claim 14, wherein the one or more sensors include a head temperature sensor configured to sense the temperature of the patient's head. A non-transitory computer-readable medium that stores one or more programs, including instructions that cause the computer to perform a method of providing pressure support therapy to a patient when performed by a computer.
The steps to generate the flow of respiratory gas to the patient,
With the step of receiving one or more inputs,
A step of estimating the patient's core body temperature for a selected time based on one or more of the inputs.
A step of adjusting the temperature of the respiratory gas provided to the patient at the selected time based on the estimated core body temperature of the patient.
Non-temporary computer readable media, including.

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